From sunshades to algal blooms, there are plenty of ideas for cooling the planet. But are there hidden dangers?
By Stephen Battersby
OOPS. We really didn’t mean to, but we seem to have broken the planet. Is there anything we can do to make it better?
Climate change is already upon us, melting ice, killing forests and making floods and heatwaves more intense. Meanwhile, global emissions of carbon dioxide and other greenhouse gases continue to increase, promising far worse to come. Even if we stopped all emissions tomorrow, temperatures would keep rising for decades, with potentially catastrophic consequences ranging from famines to rapid sea-level rise.
So perhaps it is time to get serious about the audacious idea of geoengineering. The hope is that by deliberately tinkering with our planet’s climate machine, we might be able to fix our gargantuan blunder, or at least avoid some of the most serious consequences, or just buy ourselves a bit more time to cut emissions.